Remove newPassword from share model, if disabled

It's important to delete the `newPassword` prop from the share
 model, if the user unchecks the isPasswordProtected checkbox.

This clearer and allows for the unchecking to actually work as
`this.$set()` fails with the falsy value `''`.

Signed-off-by: fenn-cs <fenn25.fn@gmail.com>

apps/files_sharing/src/views/SharingDetailsTab.vue

@@ -417,9 +417,13 @@ export default {
 					|| !!this.share.password
 			},
 			async set(enabled) {
-				// TODO: directly save after generation to make sure the share is always protected
-				this.share.password = enabled ? await GeneratePassword() : ''
-				this.$set(this.share, 'newPassword', this.share.password)
+				if (enabled) {
+					this.share.password = await GeneratePassword()
+					this.$set(this.share, 'newPassword', this.share.password)
+				} else {
+					this.share.password = ''
+					this.$delete(this.share, 'newPassword')
+				}
 			},
 		},
 		/**